﻿using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Numerics;
namespace DevisionOfTwoFactorials
{
    class Program
    {
        static public BigInteger factorial(int number)
        {
            BigInteger sum = 1;
            for (int i = 2; i <= number; i++)
            {
                sum *= i;
            }
            return sum;
        }

        static void Main(string[] args)
        {
            int N = int.Parse(Console.ReadLine());
            int K = int.Parse(Console.ReadLine());
            BigInteger multiplicationOfTwoFactorials = factorial(N) * factorial(K);
            BigInteger differenceFactorial = factorial(K - N);
            BigInteger result = multiplicationOfTwoFactorials / differenceFactorial;


            Console.WriteLine("The result is {0}", result);
            
        }
    }
}
